Recent finishing touches on the guardrails to Onion Ditch Bridge at the north edge of the West Liberty Lions Park were the last pieces Logan County Engineer Scott Coleman wanted before officially dedicating the span made of recycled plastic.

Onion Ditch Bridge on the north edge of Lions Park in West Liberty was dedicated Wednesday in a ceremony that drew about 50 people. It is the longest span bridge made from recycled plastic materials in North America and only the second on a public road. (EXAMINER PHOTO | JOEL E. MAST)

“This is the longest span made completely of 100 percent recycled plastic in North America and possibly the world,” he told about 50 people gathered Wednesday for the ceremony.

“We kept a lot of material out of landfills.”

His highway bridge crews built the bridge rather than a specialized firm.

“We did that so we would have knowledge of the material so we can handle repairs if necessary,” Mr. Coleman said.

It cost $250,000 to build the 24.6-foot span, significantly more than steel or concrete bridge. Its projected 150-year life cycle is more than three times longer than conventional materials.

Onion Ditch is only the second public roadway in the U.S. to use Axion International’s recycled structural composite system. Beams and decking are made of recycled plastic extracted from containers such as detergent bottles.

The system has been used to build bridges strong enough to carry 70-ton battle tanks and 120-ton railroad locomotives. A similar public road bridge was completed earlier this year in York, Maine.

Axion’s material also is used to replace railroad ties.

Federal Innovative Bridge Research and Deployment Program money will cover 80 percent of the project, Mr. Coleman said. The local share will be nearly equivalent to putting in a box culvert.